It is known to provide a fuel tank such as a metal fuel tank in a vehicle to hold fuel to be used by an engine of the vehicle. Typically, the fuel tank has a tank opening and a unit installed into the tank via the tank opening. An access cover is placed over the tank opening and is used to assemble and service the fuel pump and other related components. The access cover must be sealed to prevent fuel leakage and evaporative emissions. In most vehicles, the access cover is sealed with an elastomer or metal gasket, not a combination of both the elastomer and metal. An elastomer gasket is typically used to seal metal or plastic surfaces to address assembly tolerances, temperature fluctuations and pressure fluctuations encountered in normal use or extreme conditions such as a vehicle impact. The typical sealing method involves compression of the elastomeric gasket made of an elastomer such as nitrile or viton rubber. However, these materials may not be acceptable to meet zero evaporative emissions. A metal gasket has been used in production for tubing connections, for example inverted flare or compression fittings, and cylinder head gaskets.
It is desirable to provide a seal assembly for a fuel tank in a vehicle that has zero evaporative emission. It is also desirable to provide a seal assembly for a fuel tank in a vehicle that maintains sealing for assembly tolerances, temperature and pressure variation. It is further desirable to provide a seal assembly for a fuel tank in a vehicle that can be taken apart and re-sealed.